This invention relates generally to fusion of polyolefin pipes and more particularly concerns the machines used to perform the pipe fusion process.
Fusion of small diameter pipe may usually be accomplished by hand-held, stand-mounted or cart-carried fusion devices. Little, if any, heavy equipment is necessary in the performance of the fusion process. Sticks of small diameter pipe are typically manually loaded through the top or end of the device for fusion. The fusion device can often be manually disconnected and removed from the pipeline or, at worst, the pipeline is manually released and pulled from the device manually or using a relatively small motorized vehicle.
Fusion of large diameter pipe typically requires fusion machines mounted on wheeled carts or motorized vehicles and the pipe sticks and pipelines are loaded and unloaded using various types of heavy equipment. A first pipe stick is loaded onto the top of lower fixed half jaws and upper half jaws pivoted on the lower half jaws, usually manually, to clamp the first pipe stick to the fixed jaws. A second pipe stick is loaded onto the top of lower sliding half jaws and upper half jaws are pivoted on the lower jaws, usually manually, to clamp the second pipe stick to the sliding jaws. Once the fusion process is completed and the fixed and sliding jaws are opened, the fused pipeline is pulled to position the free end of second stick in the fixed jaws and a third stick is loaded onto the sliding jaws for fusion into the pipeline. The equipment for loading the pipe sticks onto the sliding jaws and pulling the pipeline from the fixed jaws is likely very heavy and expensive and requires additional operators.
It is, therefore, an object of this invention to provide a pipe fusion machine which reduces the need for use of additional heavy pipe-handling equipment in performance of the pipe fusion process. And it is an object of this invention to provide a pipe fusion machine which simplifies the pipe-handling steps of the pipe fusion process.